BackgroundProximal humeral fractures account for 5–6% of all fractures in adults. There is considerable variation in whether or not surgery is used in the management of displaced fractures involving the surgical neck.ObjectiveTo evaluate the clinical effectiveness and cost-effectiveness of surgical compared with non-surgical treatment of the majority of displaced fractures of the proximal humerus involving the surgical neck in adults.DesignA pragmatic parallel-group multicentre randomised controlled trial with an economic evaluation. Follow-up was for 2 years.SettingRecruitment was undertaken in the orthopaedic departments of 33 acute NHS hospitals in the UK. Patient care pathways included outpatient and community-based rehabilitation.ParticipantsAdults (aged ≥ 16 years) presenting within 3 weeks of their injury with a displaced fracture of the proximal humerus involving the surgical neck.InterventionsThe choice of surgical intervention was left to the treating surgeons, who used techniques with which they were experienced. Non-surgical treatment was initial sling immobilisation followed by active rehabilitation. Provision of rehabilitation was comparable in both groups.Main outcome measuresThe primary outcome was the Oxford Shoulder Score (OSS) assessed at 6, 12 and 24 months. Secondary outcomes were the 12-item Short Form health survey, surgical and other shoulder fracture-related complications, secondary surgery to the shoulder or increased/new shoulder-related therapy, medical complications during inpatient stay and mortality. European Quality of Life-5 Dimensions data and treatment costs were also collected.ResultsThe mean age of the 250 trial participants was 66 years and 192 (77%) were female. Independent assessment using the Neer classification identified 18 one-part fractures, 128 two-part fractures and 104 three- or four-part fractures. OSS data were available for 215 participants at 2 years. We found no statistically or clinically significant differences in OSS scores between the two treatment groups (scale 0–48, with a higher score indicating a better outcome) over the 2-year period [difference of 0.75 points in favour of the surgery group, 95% confidence interval (CI) –1.33 to 2.84;p = 0.479; data from 114 surgery and 117 non-surgery participants] or at individual time points. We found no statistically significant differences between surgical and non-surgical group participants in SF-12 physical or mental component summary scores; surgical or shoulder fracture-related complications (30 vs. 23 respectively); those undergoing further shoulder-related therapy, either surgery (11 vs. 11 respectively) or other therapy (seven vs. four respectively); or mortality (nine vs. five respectively). The base-case economic analysis showed that, at 2 years, the cost of surgical intervention was, on average, £1780.73 more per patient (95% CI £1152.71 to £2408.75) than the cost of non-surgical intervention. It was also slightly less beneficial in terms of utilities, although this difference was not statistically significant. The net monetary benefit associated with surgery is negative. There was only a 5% probability of surgery achieving the criterion of costing < £20,000 to gain a quality-adjusted life-year, which was confirmed by extensive sensitivity analyses.ConclusionsCurrent surgical practice does not result in a better outcome for most patients with displaced fractures of the proximal humerus involving the surgical neck and is not cost-effective in the UK setting. Two areas for future work are the setting up of a national database of these fractures, including the collection of patient-reported outcomes, and research on the best ways of informing patients with these and other upper limb fractures about initial self-care.Trial registrationCurrent Controlled Trials ISRCTN50850043.FundingThis project was funded by the NIHR Health Technology Assessment programme and will be published in full inHealth Technology Assessment; Vol. 19, No. 24. See the NIHR Journals Library website for further project information.